The Exclusionary Rule

History

The Supreme Court first addressed the issue of the admissibility of illegally obtained evidence in 1886, when it held in Boyd v. United States that the forced disclosure of papers amounting to evidence of crimes violated the constitutional right of the defendant against unreasonable search and seizure, and that such items were inadmissible in court proceedings. In 1914 the Supreme Court held in Weeks v. United States that evidence illegally obtained by federal law enforcement officers was not admissible in a federal criminal trial. Because the Weeks decision applied only to the federal government, however, state law enforcement officers were still free to seize evidence illegally without fear of its exclusion from state criminal proceedings. Moreover, evidence seized illegally by state police could be turned over to federal law enforcement officers for use in federal prosecutions because federal officers were not directly involved in the illegal seizure. In 1960, in Elkins v. United States, the Court put an end to this practice, prohibiting the introduction of illegally seized evidence in federal prosecutions regardless of whether the illegality was committed by state or federal agents.

In Wolf v. Colorado (1949), the Supreme Court applied the Fourth Amendment to the states, incorporating it into the due process clause of the Fourteenth Amendment. However, the Court refused to mandate the remedy of the exclusionary rule. Just three years later, the Court modified its position somewhat, holding in Rochin v. California that evidence seized in a manner which “shocked the conscience” must be excluded as violative of due process. Exactly what type of conduct shocked the conscience was left to be determined on a case-by-case basis. The exclusionary rule thus became applicable to state criminal proceedings, but its application was uneven.

Finally, in 1961, the Court took the step in Mapp v. Ohio that it had failed to take in Wolf: It explicitly applied the remedy of the exclusionary rule to the states. The Court did so because it acknowledged that the states had failed to provide an adequate alternative remedy for violations of the Fourth Amendment. Although there was language in Mapp that suggested the exclusionary rule originated from the Constitution, subsequent decisions indicate that the Court views the rule as a judicial means of enforcing the Fourth Amendment prohibition against unreasonable search and seizure.

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